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Regulating Charge-Transfer in Conjugated Microporous Polymer for Photocatalytic Hydrogen Evolution
摘要： Band gap engineering in donor-acceptor conjugated microporous polymers is a potential way to increase the solar energy harvesting towards photochemical water splitting. Herein, we report design and synthesis of a series of donor-acceptor CMPs [tetraphenylethylene (TPE) = donor and 9-fluorenone (F) = acceptor], F0.1CMP, F0.5CMP and F2.0CMP which exhibit tunable band gaps and photocatalytic hydrogen evolution from water. The donor-acceptor CMPs exhibit intramolecular charge transfer (ICT) absorption in the visible region (λmax=480 nm) and their band gap is finely tuned from 2.8 eV to 2.1 eV by increasing the 9-fluorenone content. Interestingly, they also show charge transfer emissions (in 540 -580 nm range), assisted by the energy transfer from the other TPE segments (not involved in CT interaction) as evidenced from fluorescence lifetime decay analysis. By increasing the 9-fluorenone content the emission color of the polymer is also tuned from green to red. Photocatalytic activities of the donor-acceptor CMPs (F0.1CMP, F0.5CMP and F2.0CMP) are greatly enhanced compared to the 9-fluorenone free polymer (F0.0CMP) which is essentially due to improved visible light absorption and low band gap of donor-acceptor CMPs. Among all the polymers F0.5CMP with an optimum band gap (2.3 eV) shows highest H2 evolution under visible light irradiation. Moreover, all the polymers show excellent dispersibility in organic solvents and also they are easily processed onto solid substrates.
关键词： Visible-light absorption,Conjugated polymers,Photocatalysis,Charge transfer,Energy transfer
更新于2025-09-23 15:23:52
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Structural diversity, magnetic properties, and luminescent sensing of four coordination polymers based on 6-(3,5-dicarboxylphenyl)nicotinic acid
摘要： Four coordination polymers (CPs), namely, [Ni(HDNA)(bibp)(H2O)]n (1), [Co(HDNA)(bibp)]n (2), {[Co(HDNA)(bibp)]·H2O}n (3) and {[Zn(HDNA)(bibp)]·H2O}n (4), have been synthesized from the mixed-ligand strategy of 6-(3,5-dicarboxylphenyl)nicotinic acid (H3DNA) and 4,4′-bis(benzimidazo-1-ly)benzene (bibp). Structural analyses revealed that four CPs all feature 2D sheets with diverse nets from {44.62}-sql net (1), {Co2(COO)2} SBUs based {44.62}-sql net (2), to 4-connected {65.8} sheet (3 & 4). Besides, the temperature-dependent magnetic susceptibilities of CPs 1-3 were investigated. And the luminescent sensing indicated CP 4 is a good bifunctional sensor for Fe3+ and Cr2O7 2- ions.
关键词： Structural diversity,Coordination polymers,Luminescent sensing,Magnetic property,Polycarboxylic acid ligand
更新于2025-09-23 15:23:52
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An eco-friendly method to enhance optical and electrical properties of conducting polymers by means of carboxymethyl cellulose
摘要： In this work, an eco-friendly method is proposed for the electro-synthesis of conductive polymers with superior optical and electrical properties by means of CMC in aqueous media. For this purpose, an aqueous dispersion of a water-insoluble monomer namely 4-amino-N-[2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl]benzamide (TPB) has been prepared by attaching it to CMC via hydrogen bonds and the conductive composite film (PTPB–CMC) has been obtained by electropolymerization. The TPB monomer has been chosen to interact with the CMC via hydrogen bonds which ensures to obtain dispersion with the CMC and also increase the compatibility of its polymer in the composite structure. As a result of the electrochemical, spectroelectrochemical investigation and surface morphology analyses of the obtained conductive polymer, it has been found that anionic CMC makes improvements in the electrical, optical and mechanical properties of the polymer by making the plasticizing effect and acting as a dopant. Furthermore, in the presence of nanocarbon materials on electrode surface, it has been determined that the polymerization potential reduced and more stable and long-lasting polymeric films which are crucial for technological applications have been obtained.
关键词： Electrochemical polymerization,Composite materials,Conducting polymers,Carboxymethyl cellulose
更新于2025-09-23 15:23:52
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Enhanced electrical conductivity of silver nanoparticles decorated fabrics with sandwich micro-structure coating layer based on “silver colloid effect”
摘要： Surface modification of nonconductor fabric substrate for enhancing electrical conductivity is a desirable work of flexible wearable devices. In our work, silver conductive layer with sandwich micro-structure was decorated on polyester fabric, and such a sandwich micro-structure layer is composed of the inner polyurethane (PU) as the interface binder, the filling layer of the precipitating silver nanoparticles (AgNPs) as the conductive path via in-situ chemical synthesis, the outer PU layer as the shielding layer. The obtained sandwich micro-structure PET fabric possessed six orders of magnitude higher conductivity than that of the case without sandwich micro-structure. Such marvelous increasing conductivity can be attributed to the “silver colloid effect” which is deemed as approximation of conductive principle of silver conductive adhesives. The present study provides a potential strategy and theoretical basis for the preparation of low concentration silver conductive fabrics.
关键词： Silver colloid effect,Nanoparticles,Quantum tunnelling effect,Sandwich micro-structure,Polymers
更新于2025-09-23 15:23:52
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Divergent Terpyridine-Based Coordination for the Construction of Photoactive Supramolecular Structures
摘要： Exploring new materials to manipulate luminescent radiation and investigate the interaction of light and matter is one of the most compelling prospects of our century. Supramolecular chemistry has unraveled the opportunity to synergistically combine the chemical and optoelectronic properties of the most diverse classes of compounds. Among these, terpyridines have acted as pivotal ligand units that enable self-assembly of multicomponent chromophoric systems. In this review we therefore elucidate the metal-coordinating ability of these materials, that promote a plethora of aggregation-induced phenomena. In particular, fluorescence tuning, reversible stimuli-responsive phosphorescence enhancement and low-dimensional complexation have been demonstrated for carbon and sulfur based terpyridine oligomeric structures. Common thread of such processes is the versatile application of light as a trigger for spectroscopic investigation and output for superior optical, medical and sensing devices.
关键词： Luminescence,Terpyridine,Supramolecular chemistry,Polymers
更新于2025-09-23 15:23:52
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Evaluating Mechanical Properties of Polymers at the Nanoscale Level via Atomic Force Microscopy–Infrared Spectroscopy
摘要： Characterization and optimization of packaging materials requires accessing their composition with nanometric precision. A possible solution comes from AFM-IR, a technique based on the coupling of Atomic Force Microscope and InfraRed spectroscopy, capable to acquire IR spectra with a spatial resolution overpassing by far the limit of infrared spectroscopy. Differentiating polyolefins – typical component of packaging films – is complicated by the large similarity in the infrared response of this class of materials. Here, we propose a method to improve domains differentiation based on the analysis of IR spectra and viscoelastic properties, extracted via a routine similar to that employed in contact-resonance AFM.
关键词： Subdiffraction Resolution,Photothermal Induced Resonance.,AFM-IR,Polymers
更新于2025-09-23 15:23:52
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Polysiloxane-based Hyperbranched Fluorescent Materials Prepared by Thiol-ene “Click” Chemistry as Potential Cellular Imaging Polymers
摘要： Hyperbranched polymers have attracted increasing interest due to their unique properties which possess excellent RI and thermal stability, and have been widely used in fields of drug delivery, catalysts, liquid crystal and so on. Herein, polysiloxane-based hyperbranched fluorescent materials (P1 and P2) were synthesized by thiol-ene “click” chemistry. Then, novel polysiloxane-based hyperbranched fluorescent materials (P1-Ln3+) has been prepared by rare earth ions coordination. In view of the splendid fluorescence characteristics and favorable stability of P1-Ln3+, it has been applied in biological imaging. P1-Ln3+ has gained commendable applications in bioimaging.
关键词： Fluorescence materials,Living cells imaging,Hyperbranched polymers,Thiol-ene "click" chemistry,Coordination,Rare earth ions
更新于2025-09-23 15:23:52
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Electrochemical properties of PEDOT: PSS /V2O5 hybrid fiber based supercapacitors
摘要： Binary conducting polymer (CP)/transition metal oxides (TMOs) fiber-based supercapacitors (FSCs) are considered to possess good electrochemical performance and cyclic stability compared with unitary ones since TMOs within FSCs can prevent the structure damage of CP during charge/discharge cycles to some extent. In this study, the CP/TMOs hybrid fibers are made by directly injecting the solution into capillary. Poly(3,4-ethylenedioxythiophene): polystyrene sulfonate /30 wt% vanadium pentoxide (PEDOT: PSS/30 wt% V2O5) fiber-based electrode has good electrochemical performance and cyclic stability (cycle retention: 94.02% after 4000 cycles at 0.1 mA/cm2). The energy density of the PEDOT: PSS/30 wt% V2O5 fiber in gel electrolyte is 1.37 μWh/cm2 at power density of 20 μW/cm2, which is much lower than the one in organic electrolyte (21.46 μWh/cm2 at power densities of 162.5 μW/cm2). Therefore, the method developed in this work induces good electrochemical performance for hybrid FSCs and promotes scalable fabrication of FSCs.
关键词： transition metal oxides,supercapacitor,Conducting polymers,electrochemical performance,hybrid fiber
更新于2025-09-23 15:23:52
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Porous Organic Polymer-Coated Band-Aids for Phototherapy of Bacteria-Induced Wound Infection
摘要： Band-Aids have been widely used for wound care. For most adhesive bandages, however, they have limited capacity to speed up the wound healing process, which in turn may cause serious wound infections. In this study, antibacterial Band-Aids, combining porphyrin based porous organic polymers (POPs) with commercial antibiotics-free Band-Aids, are designed. Under white light irradiation, POP can produce effective photothermal heat, as well as highly reactive oxygen species (ROS), thereby triggering the potent hyperthermia and simultaneous ROS increase on wounds. What's more, white-light is similar with sunlight, which makes POP-based Band-Aids (PBA) ideal wound dressings for wound disinfection.
关键词： wound infection,porous organic polymers,band-aids,white light
更新于2025-09-23 15:23:52
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Towards Porous Silicon Oxycarbide Materials: Effects of Solvents on Microstructural Features of Poly(methylhydrosiloxane)/Divynilbenzene Aerogels
摘要： We investigate the impact of solvents on the microstructure of poly(methylhydrosiloxane)/divinylbenzene (PMHS/DVB) aerogels. The gels are obtained in highly diluted conditions via hydrosilylation reaction of PMHS bearing Si-H groups and cross-linking it with C=C groups of DVB. Polymer aerogels are obtained after solvent exchange with liquid CO2 and subsequent supercritical drying. Samples are characterized using microscopy and porosimetry. Common pore-formation concepts do not provide a solid rationale for the observed data. We postulate that solubility and swelling of the cross-linked polymer in various solvents are major factors governing pore formation of these PMHS/DVB polymer aerogels.
关键词： preceramic polymers,supercritical drying,aerogel
更新于2025-09-23 15:23:52